CVE-2026-89492

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-89492", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-11T19:38:34.713Z", "datePublished": "2026-09-11T19:43:44.137Z", "dateUpdated": "2026-10-30T12:31:56.057Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-30T12:31:56.057Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nocfs2: validate directory-index entry counts when reading metadata\n\nocfs2_validate_dx_leaf() and ocfs2_validate_dx_root() check the ECC and\nsignature of an indexed-directory block before it reaches higher-level\ncallers, but neither validator bounds the ocfs2_dx_entry_list counts\nagainst the capacity of the block that holds them.\n\nocfs2_dx_dir_search() then walks\n\n\tfor (i = 0; i < le16_to_cpu(entry_list->de_num_used); i++)\n\t\tdx_entry = &entry_list->de_entries[i];\n\nover de_num_used entries with no bounds check. entry_list is either\ndx_leaf->dl_list (from ocfs2_read_dx_leaf) or, for an inline root,\ndx_root->dr_entries. A crafted on-disk image can set de_num_used (and\nde_count, which is the __counted_by_le() bound of de_entries) to 0xffff\nand make the walk read far past the end of the 4KB metadata block, giving\na slab out-of-bounds read reachable from any path lookup, stat() or open()\non an indexed directory once the image is mounted.\n\nCommit 775c17386a6f (\"ocfs2: validate dx_root extent list fields during\nblock read\") already bounds dr_list for the non-inline dx_root, but left\nthe inline dr_entries path and the dx_leaf dl_list unchecked. Add the\nsame read-time validation for both entry lists: de_count must equal the\ncapacity of the block (ocfs2_dx_entries_per_leaf()/per_root()) and\nde_num_used must not exceed de_count, rejecting corrupted metadata with\n-EFSCORRUPTED before ocfs2_dx_dir_search() can walk an out-of-range entry\narray.\n\nde_count is always written as exactly the block capacity when a leaf or\ninline root is formatted, so the equality check does not reject any valid\nimage.\n\nFound by 0sec automated security-research tooling (https://0sec.ai)."}], "metrics": [{"cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL"}, "scenarios": [{"lang": "en", "value": "AV:N - OCFS2 sets s_export_op to ocfs2_export_ops and is commonly NFS-exported on shared cluster LUNs; remote nfsd LOOKUP/GETATTR/CREATE reach ocfs2_lookup\u2192ocfs2_find_entry_dx\u2192ocfs2_dx_dir_search (and create\u2192ocfs2_dx_entry_list_insert) over the network with no local syscall on the server.\nAC:L - The attacker fully controls on-disk de_num_used and de_count in a dx_root or dx_leaf; inflating them above the fixed 4K-block capacity (e.g. 0xffff with de_num_used still below de_count) deterministically overflows the entry walk and insert with no race or attacker-uncontrollable layout.\nPR:N - Triggering needs only NFS LOOKUP or CREATE on an exported directory, including guest or anonymous NFS, or any unprivileged accessor of a mounted volume holding the forged index; planting malformed directory-index metadata on shared cluster storage does not require init-namespace root on the victim.\nUI:N - Once the OCFS2 volume is mounted and NFS-exported as a normal cluster or NAS deployment, the attacker triggers the overflow by their own LOOKUP, stat, open, or CREATE; no additional victim action such as mounting an image or opening a file is required.\nS:U - The overflow corrupts kernel memory and OCFS2 metadata on the host that parses the forged directory index; it does not escape a VM, bypass an IOMMU, or otherwise cross into a separate security authority.\nC:H - ocfs2_dx_dir_search walks de_num_used with no capacity check, so de_num_used of 0xffff reads far past the 4KB metadata block (up to about 1 MiB of adjacent kernel memory), an unbounded out-of-bounds read that enables high-impact disclosure.\nI:H - When de_count is inflated past block capacity and de_num_used is still less than de_count, create/mkdir calls ocfs2_dx_entry_list_insert and writes a dx_entry at de_entries[de_num_used] past the block; unlink memmove is similarly unbounded, yielding an attacker-triggered kernel out-of-bounds write.\nA:H - The unbounded out-of-bounds read on lookup and out-of-bounds write on create against kernel metadata buffers cause a kernel oops or panic, fully denying availability of the OCFS2 node until reboot."}]}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/ocfs2/dir.c"], "versions": [{"version": "9b7895efac906d66d19856194e1ba61f37e231a4", "lessThan": "3f28574dd59672ac47f3110c9a8ead703ec021c0", "status": "affected", "versionType": "git"}, {"version": "9b7895efac906d66d19856194e1ba61f37e231a4", "lessThan": "3497aa757788de5d904f41814f1df0b292a8be09", "status": "affected", "versionType": "git"}, {"version": "9b7895efac906d66d19856194e1ba61f37e231a4", "lessThan": "47b8152ed7709f7ef30b398fb0bfe4b452dd0495", "status": "affected", "versionType": "git"}, {"version": "9b7895efac906d66d19856194e1ba61f37e231a4", "lessThan": "aad3129b8e915d0ff492bb7517d825d8490cfdd9", "status": "affected", "versionType": "git"}, {"version": "9b7895efac906d66d19856194e1ba61f37e231a4", "lessThan": "5e661f55ca8568471fce558effe81cca112f5cb2", "status": "affected", "versionType": "git"}, {"version": "9b7895efac906d66d19856194e1ba61f37e231a4", "lessThan": "fcfcba8fe17dbf2c8805690b8cc25e32d81249a4", "status": "affected", "versionType": "git"}, {"version": "9b7895efac906d66d19856194e1ba61f37e231a4", "lessThan": "b8a5c0c32df2c5b685ceef76ac77e37c7e1dc3ed", "status": "affected", "versionType": "git"}, {"version": "9b7895efac906d66d19856194e1ba61f37e231a4", "lessThan": "bc70726ddad53c7e9a9a85915bf2415b0d4f42f9", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/ocfs2/dir.c"], "versions": [{"version": "2.6.30", "status": "affected"}, {"version": "0", "lessThan": "2.6.30", "status": "unaffected", "versionType": "semver"}, {"version": "5.10.273", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.224", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.191", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.160", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.111", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.51", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2.4", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.3", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "5.10.273"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "5.15.224"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "6.1.191"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "6.6.160"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "6.12.111"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "6.18.51"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "7.2.4"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "2.6.30", "versionEndExcluding": "7.3"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/3f28574dd59672ac47f3110c9a8ead703ec021c0"}, {"url": "https://git.kernel.org/stable/c/3497aa757788de5d904f41814f1df0b292a8be09"}, {"url": "https://git.kernel.org/stable/c/47b8152ed7709f7ef30b398fb0bfe4b452dd0495"}, {"url": "https://git.kernel.org/stable/c/aad3129b8e915d0ff492bb7517d825d8490cfdd9"}, {"url": "https://git.kernel.org/stable/c/5e661f55ca8568471fce558effe81cca112f5cb2"}, {"url": "https://git.kernel.org/stable/c/fcfcba8fe17dbf2c8805690b8cc25e32d81249a4"}, {"url": "https://git.kernel.org/stable/c/b8a5c0c32df2c5b685ceef76ac77e37c7e1dc3ed"}, {"url": "https://git.kernel.org/stable/c/bc70726ddad53c7e9a9a85915bf2415b0d4f42f9"}], "title": "ocfs2: validate directory-index entry counts when reading metadata", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/ocfs2/dir.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "3f28574dd59672ac47f3110c9a8ead703ec021c0", "status": "affected", "version": "9b7895efac906d66d19856194e1ba61f37e231a4", "versionType": "git"}, {"lessThan": "3497aa757788de5d904f41814f1df0b292a8be09", "status": "affected", "version": "9b7895efac906d66d19856194e1ba61f37e231a4", "versionType": "git"}, {"lessThan": "47b8152ed7709f7ef30b398fb0bfe4b452dd0495", "status": "affected", "version": "9b7895efac906d66d19856194e1ba61f37e231a4", "versionType": "git"}, {"lessThan": "aad3129b8e915d0ff492bb7517d825d8490cfdd9", "status": "affected", "version": "9b7895efac906d66d19856194e1ba61f37e231a4", "versionType": "git"}, {"lessThan": "5e661f55ca8568471fce558effe81cca112f5cb2", "status": "affected", "version": "9b7895efac906d66d19856194e1ba61f37e231a4", "versionType": "git"}, {"lessThan": "fcfcba8fe17dbf2c8805690b8cc25e32d81249a4", "status": "affected", "version": "9b7895efac906d66d19856194e1ba61f37e231a4", "versionType": "git"}, {"lessThan": "b8a5c0c32df2c5b685ceef76ac77e37c7e1dc3ed", "status": "affected", "version": "9b7895efac906d66d19856194e1ba61f37e231a4", "versionType": "git"}, {"lessThan": "bc70726ddad53c7e9a9a85915bf2415b0d4f42f9", "status": "affected", "version": "9b7895efac906d66d19856194e1ba61f37e231a4", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["fs/ocfs2/dir.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "2.6.30"}, {"lessThan": "2.6.30", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "5.10.*", "status": "unaffected", "version": "5.10.273", "versionType": "semver"}, {"lessThanOrEqual": "5.15.*", "status": "unaffected", "version": "5.15.224", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.191", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.160", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.111", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.51", "versionType": "semver"}, {"lessThanOrEqual": "7.2.*", "status": "unaffected", "version": "7.2.4", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.3", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nocfs2: validate directory-index entry counts when reading metadata\n\nocfs2_validate_dx_leaf() and ocfs2_validate_dx_root() check the ECC and\nsignature of an indexed-directory block before it reaches higher-level\ncallers, but neither validator bounds the ocfs2_dx_entry_list counts\nagainst the capacity of the block that holds them.\n\nocfs2_dx_dir_search() then walks\n\n\tfor (i = 0; i < le16_to_cpu(entry_list->de_num_used); i++)\n\t\tdx_entry = &entry_list->de_entries[i];\n\nover de_num_used entries with no bounds check. entry_list is either\ndx_leaf->dl_list (from ocfs2_read_dx_leaf) or, for an inline root,\ndx_root->dr_entries. A crafted on-disk image can set de_num_used (and\nde_count, which is the __counted_by_le() bound of de_entries) to 0xffff\nand make the walk read far past the end of the 4KB metadata block, giving\na slab out-of-bounds read reachable from any path lookup, stat() or open()\non an indexed directory once the image is mounted.\n\nCommit 775c17386a6f (\"ocfs2: validate dx_root extent list fields during\nblock read\") already bounds dr_list for the non-inline dx_root, but left\nthe inline dr_entries path and the dx_leaf dl_list unchecked. Add the\nsame read-time validation for both entry lists: de_count must equal the\ncapacity of the block (ocfs2_dx_entries_per_leaf()/per_root()) and\nde_num_used must not exceed de_count, rejecting corrupted metadata with\n-EFSCORRUPTED before ocfs2_dx_dir_search() can walk an out-of-range entry\narray.\n\nde_count is always written as exactly the block capacity when a leaf or\ninline root is formatted, so the equality check does not reject any valid\nimage.\n\nFound by 0sec automated security-research tooling (https://0sec.ai)."}], "id": "CVE-2026-89492", "lastModified": "2026-10-30T13:20:18.043", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 9.8, "baseSeverity": "CRITICAL", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 5.9, "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "type": "Secondary"}]}, "published": "2026-09-11T20:19:31.090", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/3497aa757788de5d904f41814f1df0b292a8be09"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/3f28574dd59672ac47f3110c9a8ead703ec021c0"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/47b8152ed7709f7ef30b398fb0bfe4b452dd0495"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/5e661f55ca8568471fce558effe81cca112f5cb2"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/aad3129b8e915d0ff492bb7517d825d8490cfdd9"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/b8a5c0c32df2c5b685ceef76ac77e37c7e1dc3ed"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/bc70726ddad53c7e9a9a85915bf2415b0d4f42f9"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/fcfcba8fe17dbf2c8805690b8cc25e32d81249a4"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: Linux kernel: OCFS2 out-of-bounds read via crafted directory-index entries", "id": "2532489", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2532489"}, "csaw": false, "cvss3": {"cvss3_base_score": "4.1", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-125", "details": ["A flaw was found in the Linux kernel's OCFS2 filesystem. A local attacker with the ability to mount a crafted on-disk image could exploit this vulnerability by providing excessive directory-index entry counts when reading metadata. This can lead to an out-of-bounds read, potentially causing information disclosure or a system crash."], "name": "CVE-2026-89492", "public_date": "2026-09-11T19:43:44Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-89492\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-89492\nhttps://git.kernel.org/stable/c/b8a5c0c32df2c5b685ceef76ac77e37c7e1dc3ed\nhttps://git.kernel.org/stable/c/bc70726ddad53c7e9a9a85915bf2415b0d4f42f9\nhttps://git.kernel.org/stable/c/fcfcba8fe17dbf2c8805690b8cc25e32d81249a4"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[9b7895efac906d66d19856194e1ba61f37e231a4,fcfcba8fe17dbf2c8805690b8cc25e32d81249a4)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[9b7895efac906d66d19856194e1ba61f37e231a4,b8a5c0c32df2c5b685ceef76ac77e37c7e1dc3ed)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[9b7895efac906d66d19856194e1ba61f37e231a4,bc70726ddad53c7e9a9a85915bf2415b0d4f42f9)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "2.6.30"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,2.6.30)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.51,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.2.4,7.3.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[7.3-rc1,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-09-12T13:45:14.872795+00:00", "updated": "2026-09-15T22:45:07.202760+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"]}